Israel's government is urging Israelis visiting Egypt's Sinai peninsula to leave immediately because of what it calls an imminent terrorist attack.

Israel's anti-terrorism office says it has "concrete" evidence of a plot to kidnap Israelis in the Sinai and smuggle them to the Gaza Strip. Israeli officials called on family members to contact Israelis vacationing on the peninsula and ask them to return to Israel right away.

Some 20,000 Israelis traveled to the Sinai during the recent Jewish Passover holiday, despite prior Israeli warnings of possible terrorist attacks there. Many vacationers have since returned to Israel.

The Sinai has been the scene of terrorist attacks on Israelis and Western tourists. In 2004, suicide bombers attacked a Sinai hotel and several campsites popular with Israelis, killing 34 people and wounding more than 120.